It has been proposed to mount inflatable bags on or attach them to vehicle seat belts (U.S. Pat. Nos. 5,135,256 and 5,161,821). In these proposals the inflatable member is positioned around the belt and is not attached to any part of the vehicle other than the belt itself. As the member inflates it does not substantially change its position relative the belt. In another proposal an inflatable bag is positioned around a lap belt and not attached to the belt (U.S. Pat. No. 5,871,230). This proposed system permits the occupant to slide the inflated bag side-to-side on the belt to center it prior to inflation. Once the inflatable bag is positioned it remains in that position when inflated.
Broadly, the present invention comprises an arrangement and its method of installation and operation in which a shaped inflatable member is stored adjacent a vehicle seat belt. Upon detection of a collision the inflatable member is inflated. As it deploys it is guided by the seat belt or portion thereof when the occupant is buckled-up. The invention includes an inflatable member and a device to accomplish inflation which inflatable member is preferably positioned around the seat belt or portion thereof. The inflatable member when positioned and actuated serves to protect the occupant. The inflatable member is mounted adjacent the belt prior to inflation and the inflated member travels around or along the belt when the occupant is buckled-up. After full inflation the inflated member reaches its predetermined protective position.
It is also a feature that the present invention functions when the seat belt is in its unbuckled or inactive position. The unbuckled belt is guided by the inflatable member as deployed to provide protection.
Inflation of the member including its travel along the buckled-up belt portion accomplishes pre-tightening of the belt to retard or reverse occupant movement just prior to and during deceleration of the vehicle.
The present invention is useful with any belt system such as a three point system with lap and torso portion, a four or five point harness system, as well as a two point lap belt system. The inflatable member, the inflator, the crash sensor and other associated equipment may be enclosed in a modular unit which may be mounted adjacent portions of the safety belt arrangement. Bags protect the head, neck, shoulder, torso, lap or leg of the occupant.